Vehicular imaging system with controlled illumination device and camera

ABSTRACT

An imaging system of a vehicle includes a tail lamp assembly that illuminates a field of illumination rearward of the vehicle. A light source control operates at least one light source of the tail lamp assembly in a repeating cycle that includes (i) a first illumination period wherein light emitted by the tail lamp assembly has a first brightness level and (ii) a second illumination period wherein light emitted by the tail lamp assembly has a second brightness level that is lower than the first brightness level. A camera is operable to capture image data representative of a region that is at least in part encompassed by the field of illumination. A camera control may operate the camera to capture image data during at least part of the first illumination period and to not capture image data during at least part of the second illumination period.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 12/693,681, filed Jan. 26, 2010, now U.S. Pat. No. 8,964,032,which claims the benefits of U.S. provisional application Ser. No.61/148,457, filed Jan. 30, 2009.

FIELD OF THE INVENTION

The present invention relates to an illumination system for the rear ofa vehicle, and more particularly to an illumination system that is usedin conjunction with a back-up camera at the rear of a vehicle.

BACKGROUND OF THE INVENTION

Illumination systems for illuminating rearwardly behind a vehiclegenerally suffer from several problems. A first problem is that atypical system does not provide strong illumination and does notilluminate a field of view that extends very far behind the vehicle.However, government regulations in some jurisdictions limit the amountof illumination that can be provided in an effort to protect onlookers,such as drivers of other vehicles from being blinded or otherwisedistracted by such illumination. It would be advantageous to be able tobetter illuminate rearwardly behind a vehicle without significantlydistracting onlookers.

Additionally, some vehicles are equipped with back-up cameras, however,with the poor illumination provided by a typical rear illuminationsystem, the back-up camera may not be able to gather enough light toprovide useful information to the driver of the vehicle. It would beadvantageous to be able to assist the camera in providing usefulinformation to the driver.

SUMMARY OF THE INVENTION

In a first aspect, the invention is directed to an illumination systemfor rearward illumination for a first vehicle. The illumination systemincludes a tail lamp assembly, a sensor and a controller for controllingthe operation of the tail lamp assembly. If the controller determinesthat there are any oncoming second vehicles behind the first vehiclethat are sufficiently close to the first vehicle, then the controlleroperates the tail lamp assembly in one mode. If the controllerdetermines that there are no oncoming second vehicles behind the firstvehicle that are sufficiently close to the first vehicle, then thecontroller permits the operation of the tail lamp assembly in anothermode.

In one embodiment of the first aspect, the tail lamp assembly isoperable in the first mode to cast light over a first field ofillumination, and in the second mode to cast light over a second fieldof illumination that extends farther from the first vehicle than thefirst field of illumination. The controller is configured to receivesignals from the sensor and to make a determination of whether there areany oncoming second vehicles behind the first vehicle that are closerthan a selected threshold proximity to the first vehicle, and whereinthe controller is configured to operate the tail lamp assembly in thefirst mode based at least in part on if the determination is positive.

In a second aspect, the invention is directed to an illumination systemfor rearward illumination for a vehicle, including a tail lamp assemblyconfigured to cast light on a field of illumination, a tail lampassembly controller configured to operate the tail lamp assembly in arepeating cycle that includes a first illumination period wherein thetail lamp assembly has a first brightness level, and a secondillumination period wherein the tail lamp assembly has a secondbrightness level that is lower than the first brightness level, at afrequency that may be sufficient for an onlooker to see the tail lampassembly as being continuously lit at a third brightness level that isbetween the first and second brightness levels. A camera is provided andis configured to receive video input from at least part of the field ofillumination. A camera controller is provided and is configured to causethe camera to send camera signals related to video input received by thecamera to a camera signal receiver during at least part of the firstillumination period and to stop the camera from sending camera signalsto the camera signal receiver during at least part of the secondillumination period. The camera signal receiver may send the camerasignals to one or more other devices such as a display, a signalprocessor, and an obstruction detection processor.

In a third aspect, the invention is directed to an illumination systemfor rearward illumination for a vehicle, including a tail lamp assemblyconfigured to cast light on a field of illumination, a tail lampassembly controller configured to operate the tail lamp assembly in arepeating cycle that includes a first illumination period wherein thetail lamp assembly has a first brightness level, and a secondillumination period wherein the tail lamp assembly has a secondbrightness level that is lower than the first brightness level, a cameraconfigured to receive video input from at least part of the field ofillumination, and a camera signal processor that is configured toreceive camera signals from the camera and to process the camera signalsto remove portions thereof corresponding to video input received by thecamera during the second illumination period. The camera signalprocessor may send the processed camera signals to one or more otherdevices such as a display and an obstruction detection processor.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described by way of example only withreference to the attached drawings, in which:

FIG. 1 is a side view of a vehicle equipped with an illumination systemin accordance with an embodiment of the present invention, wherein theillumination system includes a tail lamp assembly operating in a firstmode;

FIG. 2 is a side view of the vehicle shown in FIG. 1, with the tail lampassembly operating in a second mode;

FIG. 3 is a magnified side view of a tail lamp assembly that may be usedin the illumination system shown in FIG. 1;

FIG. 4 is a magnified side view of an alternative tail lamp assemblythat may be used in the illumination system shown in FIG. 1;

FIG. 5 is an exemplary image from video input that received by a camerathat is part of the illumination system shown in FIG. 1;

FIG. 6 is a side view of a vehicle equipped with an illumination systemin accordance with another embodiment of the present invention;

FIG. 7 is a graph illustrating the operation of elements from theillumination system shown in FIG. 6; and

FIG. 8 is a side view of a vehicle equipped with an illumination systemin accordance with yet another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference is made to FIG. 1, which shows an illumination system 10 forrearward illumination for a first vehicle 12. The illumination system 10assists a vehicle driver to see when driving the first vehicle 12 inreverse, while having a low impact on drivers of other vehicles that maybe behind the first vehicle 12.

The illumination system 10 includes a tail lamp assembly 14, a sensor 16and a controller 18. The tail lamp assembly 14 is operable in twodifferent modes, illustrated in FIGS. 1 and 2. The first mode is shownin FIG. 1, and is the mode wherein the tail lamp assembly 14 operateswith to cast light over a first field of illumination, shown at 20. Thefirst field of illumination 20 may be angled downwards from the firstvehicle 12 so as to illuminate an area of the road that is severalmeters behind the first vehicle 12. The tail lamp assembly 14 mayoperate at a first brightness level when in the first mode. The firstbrightness level and the first field of illumination 20 are selected tomake it relatively unlikely to blind drivers of any oncoming secondvehicles shown at 22 that are behind the first vehicle 12 when the taillamp assembly 14 is in the first mode.

The second field of illumination is shown at 24 in FIG. 2. The secondfield of illumination 24 is selected to extend farther behind the firstvehicle 12 than the first field of illumination 24. The upper edge ofthe second field of illumination 24 is shown at 26 and may extendapproximately along or above the horizontal (shown at H) therebyilluminating the road generally behind the first vehicle 12. The secondbrightness level may be selected to be relatively strong so as to assistin providing illumination that extends relatively farther down the roadthan when the tail lamp assembly 14 is in the first mode.

An exemplary embodiment of the tail lamp assembly 14 is shown in moredetail in FIG. 3. The tail lamp assembly 14 may include a first taillamp 28 that is illuminated when the tail lamp assembly 14 is in thefirst mode and a second tail lamp 30 that is illuminated (either aloneor in addition to the first tail lamp 28) when the tail lamp assembly 14is in the second mode. The tail lamp assembly 14 may further include afirst reflector 32 positioned to direct light emitted by the first taillamp 28 and a second reflector 34 that is positioned to direct light bythe second tail lamp 30. The first reflector 32 may be configured todirect light from the first tail lamp 28 to illuminate the first fieldof illumination 20 (FIG. 1). In an embodiment wherein only the secondtail lamp 30 (FIG. 3) is illuminated when the tail lamp assembly 14 isin the second mode, the second reflector 34 may be configured to directlight from the second tail lamp 30 about the entirety of the secondfield of illumination 24 (FIG. 2). In an embodiment wherein both thefirst and second tail lamps 28 and 30 (FIG. 3) are illuminated when thetail lamp assembly is in the second mode, the second reflector 34 may beconfigured to direct light from the second tail lamp 30 about a selectedportion of the second field of illumination 24 (FIG. 2), while the firstreflector 32 (FIG. 3) directs light from the first tail lamp 28 aboutanother selected portion of the second field of illumination 24 (FIG.2).

The tail lamps 28 and 30 may be any suitable type of lamps. For example,one or both of the tail lamps 28 and 30 may be made up of light emittingdiodes (LEDs), halogen bulbs, high intensity discharge bulbs, or anycombination thereof.

Instead of having first and second tail lamps 28 and 30, the tail lampassembly 14 may have a single tail lamp 36 shown in FIG. 4, thatprovides the illumination for both the first mode and the second mode.The single tail lamp 32 may be a halogen bulb that includes a firstfilament 38 that is illuminated when the tail lamp assembly 14 is in thefirst mode and a second filament 40 that is illuminated (either inaddition to, or instead of, the first filament 38) when the tail lampassembly 14 is in the second mode. The first and second filaments 38 and40 may be positioned to cooperate with a reflector 42 that is configuredto direct light from them as needed to illuminate the first and secondfields of illumination 20 and 24 (FIGS. 1 and 2 respectively).

Referring to FIG. 1, the sensor 16 is positioned to sense the presenceof oncoming second vehicles 22 that are behind the first vehicle 12, andmay have any suitable structure for this purpose. For example, thesensor 16 may be a camera 44 that faces rearwardly on the first vehicle12. The camera 44 receives video input and sends camera signals relatedto the received video input to the controller 18.

The controller 18 is configured to receive the camera signals and tomake a determination as to whether there are any second vehicles 22behind the tail lamp assembly 14 that are closer than a selectedproximity shown at P. Additionally, the controller 18 may also makedeterminations regarding one or more other criteria, such as, forexample, the angles of any oncoming second vehicles 22 in relation tothe first vehicle 12. If the determination made by the controller 18 ispositive (i.e., it determines that there are one or more oncoming secondvehicles 22 that are closer than the threshold proximity P), thecontroller 18 puts the tail lamp assembly 14 into the first mode so asnot to blind the drivers of those other second vehicles 22. If thedetermination is negative, the controller 18 permits the tail lampassembly 14 to be operated in the second mode. For example, upon makinga negative determination the controller 18 would permit the driver ofthe first vehicle 12 to activate the second mode for the tail lampassembly 14 via a control switch in the vehicle cabin (not shown).Alternatively, upon a negative determination the controller 18 may beconfigured to by itself activate the second mode for the tail lampassembly 14.

The selected proximity P may be any suitable value. For example, thevalue of P may be effectively infinity. In other words, the controller18 may be configured to switch the tail lamp assembly 14 to the firstmode upon determining that any oncoming second vehicles 22 are behindthe tail lamp assembly 14 regardless of their distance from the taillamp assembly 14. As an alternative, the selected proximity P may beselected to prompt a positive determination by the controller 18 if anoncoming second vehicle 22 is within the second field of illumination 24(FIG. 2). In other words, the controller 18 may be configured to switchthe tail lamp assembly 14 to the first mode upon determining that anyoncoming second vehicles are within the second field of illumination(FIG. 2).

FIG. 5 shows an exemplary image 46 from the video input received by thecamera 44. The controller 18 may detect oncoming second vehicles 22 bydetermining if the image 46 received by the camera 44 contains anyheadlight images, examples of which are shown at 48. Oncoming secondvehicle headlights, shown at 50 in FIGS. 1 and 2, may for example, havea characteristic appearance when appearing as headlight images 48 (FIG.5) in the video input received by the camera 44 (FIG. 1). Thischaracteristic appearance may be detectable by the controller 18. Thecontroller 18 may be further configured to determine the approximatedistance of any detected vehicle headlights 50 to the tail lamp assembly14. For example, the controller 18 may estimate the distance of anydetected vehicle headlights 50 based at least in part on the size of theheadlight images 48 (FIG. 5) and on the apparent brightness level of theheadlight images 48. A relatively larger and/or brighter headlight image48 may be interpreted as being indicative of an oncoming second vehicle22 (FIG. 1) that is relatively closer to the tail lamp assembly 14,while a relatively smaller and/or less bright headlight image 48 (FIG.5) may be interpreted as being indicative of an oncoming second vehicle22 (FIG. 1) that is relatively farther from the first vehicle 12.

In addition to being used to sense the presence of oncoming vehicles 22from behind, the camera 44 may also send camera signals for use indisplaying video output on a display shown at 52 inside the vehiclecabin (not shown).

By providing the rearview illumination system 10, the vehicle driver canmore safely back the first vehicle 12 up with increased capability tosee obstructions behind the first vehicle 12 while maintaining arelatively low impact on drivers in any oncoming second vehicles 22 thatare behind the first vehicle 12 by keeping the tail lamp assembly 14 ina first mode that is less likely to blind drivers of second vehicles 22.In embodiments wherein the camera 44 is connected to the display 52, therearview illumination system 10 is also advantageous, since the videooutput that is displayed on the display 52 can be particularly improvedby the illumination provided when the tail lamp assembly 14 is in thesecond mode.

Reference is made to FIG. 6, which shows an illumination system 60 forrearward illumination for a first vehicle 62 in accordance with anotherembodiment of the present invention. The illumination system 60 isconfigured to provide a relatively highly illuminated video output thatis used for purposes of identification of obstructions behind the firstvehicle, while having a relatively low brightness when seen by onlookersbehind the first vehicle 62 including pedestrians and drivers ofoncoming second vehicles 64 that are behind the first vehicle 62. Theillumination system 60 includes a tail lamp assembly 64, a tail lampassembly controller 66, a camera 68 and a camera controller 70, a camerasignal receiver 72, a camera signal processor 74 and a display 76.

The tail lamp assembly 64 is configured to cast light on a field ofillumination 77, which may have any suitable size and shape. The taillamp assembly 64 includes a tail lamp 78 and optionally further includesa reflector 80 configured to assist in directing light from the taillamp 78 about the field of illumination 77. The tail lamp 78 may includeany type of light emitting element. For example, the tail lamp 78 mayinclude a plurality of LEDs, or a halogen bulb, or a high-intensitydischarge (HID) bulb.

With reference to FIGS. 6 and 7, the tail lamp assembly controller 66 isconfigured to operate the tail lamp assembly 64 in a repeating cycleshown at P in FIG. 7, that includes a first illumination period P1wherein the tail lamp assembly 64 has a first brightness level B1, and asecond illumination period P2 wherein the tail lamp assembly 64 has asecond brightness level B2 that is lower than the first brightness levelB1. The cycle P of first and second brightness levels B1 and B2 may berepeated at a selected frequency F (not shown in the figures). When thefrequency F is sufficiently high the tail lamp assembly 64 may appear toan onlooker as being lit at a constant third brightness level, which isshown in FIG. 7 at B3, which is between the first and second brightnesslevels B1 and B2. Specifically, the third brightness level mayapproximately be a weighted average brightness level between B1 and B2taking into account the lengths of the first and second illuminationperiods P1 and P2. It is preferable that the cycle P is repeated at theaforementioned sufficiently high frequency so that the tail lampassembly 64 appears to be lit with a constant third brightness B3 toonlookers.

The first brightness level B1 may be selected to be sufficiently brightto permit the camera to receive video input with a selected amount ofdetail, but may be considered excessively bright to onlookers if thetail lamp assembly 64 were operated solely at the first brightness levelB1. The second brightness level B2 may be selected to be zero. In otherwords, the tail lamp assembly 64 may be off during the secondillumination period P2. The first illumination period P1 is preferablyselected to be as large as possible while keeping the weighted averagebrightness B3 sufficiently low to avoid blinding an onlooker, such as adriver of an oncoming second vehicle that is behind the first vehicle62.

In the exemplary embodiment shown in FIG. 7, the first illuminationperiod P1 may be selected to be approximately 1/120th of a second (i.e.,0.0083 seconds), and the second illumination period P2 may be selectedto be approximately 3/120ths of a second (i.e., 0.025 seconds),providing a frequency of 30 cycles P per second (i.e., 30 Hz). It istheorized that a frequency of about 30 Hz is sufficient for an onlookerto see the tail lamp assembly 64 as being lit at a constant brightnesslevel. Accordingly, a frequency of at least about 30 Hz is theorized asbeing advantageous.

The camera 68 is configured to receive video input from at least part ofthe field of illumination 77. The camera controller 70 may be configuredto cause the camera 68 to send camera signals related to video inputreceived by the camera 68 to the camera signal receiver 72 during atleast part of the first illumination period P1 and to stop the camera 68from sending camera signals to the camera signal receiver 72 during atleast part of the second illumination period P2. In the embodiment shownin FIG. 6, the camera controller 70 is configured to cause the camera 68to send camera signals relating to video input received by the camera 68during all of the first illumination period P1. To ensure that all ofthe video input during the first illumination period P1 is captured, thecamera 68 may send camera signals during a camera sending period Pc(shown in FIG. 7) that begins slightly earlier than the start of thefirst illumination period P1 and ends slightly after the end of thefirst illumination period P1.

The camera controller 70 may receive timing signals from the tail lampassembly controller 66 that are indicative of when to cause the camera68 to send camera signals and when to stop the camera 68 from sendingcamera signals.

The camera signal receiver 72 receives the camera signals and passesthem on to the camera signal processor 74, which is configured toprocess the camera signals to remove any portions thereof correspondingto video input received by the camera 68 during the second illuminationperiod P2 (i.e., when the tail lamp assembly 64 is at the second, (i.e.,lower) brightness level). By removing those portions, the remainingcamera signals correspond to video input received by the camera 68 onlyduring the first illumination period P1 (i.e., when the tail lampassembly 64 is at the first (i.e., higher) brightness level). Performingthe processing steps to remove video input from the second period P2results in processed camera signals, which may be sent to the display 76for viewing by a driver of the vehicle 62. Alternatively oradditionally, the processed camera signals may be further processed byan obstruction detection processor 82 to determine if there is anobstruction present behind the vehicle 62 that should be brought to theattention of the driver. For example, the obstruction detectionprocessor 82 may be configured to further process the processed camerasignals, to produce secondarily processed camera signals, thatcorrespond to a displayed video output that includes an icon at theposition of a detected obstruction to bring the detected obstruction tothe attention of the driver.

The camera signal processor 74, the camera controller 70 and theobstruction detection processor 82 are shown in FIG. 6 to be the samedevice. It is alternatively possible, however, for one or more of thecamera signal processor 74, the camera controller 70 and the obstructiondetection processor 82 to be a separate device from the others.

By controlling the illumination of the tail lamp assembly 64 between thefirst and second brightness levels B1 and B2 as described above, and bycontrolling the operation of the camera 68 as described above,relatively bright video output may be provided on the display 76 inembodiments wherein the display 76 is provided, and the obstructiondetection processor 82 may be able to more easily detect obstructionsthat would be relatively difficult to detect in low light conditions, inembodiments wherein the obstruction detection processor 82 is provided,while appearing to onlookers as having a selected lower brightness level(i.e., the third brightness level B3) that is less likely than the firstbrightness level B1 to be considered excessively bright.

Reference is made to FIG. 8 which shows an alternative illuminationsystem 90 that is similar to the illumination system 60 (FIG. 6), butwherein there is no camera signal processor, and instead the camerasignals are sent from the camera signal receiver 72 directly to thedisplay 76. In this alternative, portions of the video output displayedby the display 76 may be based on video input to the camera 68 duringthe second illumination period P2 (FIG. 7). In such instances thedisplayed video output may not appear as bright as the displayed videooutput that results when the camera signal processor 74 removes theportions of the camera signals that are based on video input to thecamera 68 during the second illumination period P2 (FIG. 7). It isoptionally possible however for the camera controller 70 to operate thecamera 68 to send camera signals during a camera sending period Pc thatis selected to be within the first illumination period P1 (FIG. 7), sothat the displayed video output on the display 76 is bright even withoutprocessing by a camera signal processor.

The display 76 in both the embodiments shown in FIGS. 6 and 8 isconfigured to display video output based on the camera signals sent bythe camera 68 to the camera signal receiver 72. The displayed videooutput may correspond substantially exactly to the camera signals sentby the camera 68 to the camera signal receiver 72, as is the case forthe illumination system 90 shown in FIG. 8. Alternatively the displayedvideo output may correspond substantially exactly to the processedcamera signals sent by the camera signal processor 74 in the embodimentshown in FIG. 6, which are themselves based on the camera signals.

It will be noted that the frequency F of the operation of the tail lampassembly 64 (FIGS. 6 and 8) controls the frequency of the camerasignals, which, in turn means that the display 76 may display videooutput at the frequency F. For the example illumination periods P1 andP2 (FIG. 7) given above (i.e., P1=1/120th of a second and P2=3/120ths ofa second) and in an embodiment wherein all of the video input during theperiod P1 is captured and sent to the display 76 (FIGS. 6 and 8), thedisplay 76 will receive video signals corresponding to video clipslasting 1/120th of a second every 1/30th of a second. When displayed,such video output may nonetheless appear free of discontinuities to thevehicle driver, even though 3/120ths of every 1/30th of second areabsent from the video output (because during that period the tail lampassembly 64 is at the second (i.e., lower) brightness level B2).

The term ‘a tail lamp assembly’ as used herein, and particularly in theaccompanying claims, is not intended to be limited to a quantity of one.In other words, it is optionally possible for a plurality of tail lampassemblies to be controlled or operated as part of the illuminationsystems described herein. It is contemplated that in many instances twotail lamp assemblies would be provided as part of an illumination systemon a vehicle with one tail lamp assembly on each side of the vehicle'slongitudinal centerline.

While the above description constitutes a plurality of embodiments ofthe present invention, it will be appreciated that the present inventionis susceptible to further modification and change without departing fromthe fair meaning of the accompanying claims.

1. An imaging system for capturing images rearward of a vehicle, theimaging system comprising: a tail lamp assembly configured for mountingat a rear portion of a vehicle equipped with the imaging system, whereinthe tail lamp assembly includes at least one light source operable toemit light and wherein, with the tail lamp assembly mounted at theequipped vehicle and with the at least one light source activated, thetail lamp assembly emits light that illuminates a field of illuminationrearward of the equipped vehicle; a light source control operable tooperate at least one light source of the tail lamp assembly in arepeating cycle that includes (i) a first illumination period whereinlight emitted by the tail lamp assembly has a first brightness level,and (ii) a second illumination period wherein light emitted by the taillamp assembly has a second brightness level that is lower than the firstbrightness level; a camera operable to capture image data representativeof a region that is at least in part encompassed by the field ofillumination; and a camera control operable to control the camera,wherein the camera control operates the camera to capture image dataduring at least part of the first illumination period and wherein thecamera control operates the camera to not capture image data during atleast part of the second illumination period.
 2. The imaging system ofclaim 1, wherein the light source control deactivates the at least onelight source of the tail lamp assembly during the second illuminationperiod.
 3. The imaging system of claim 1, wherein the camera controloperates the camera to not capture image data during the secondillumination period.
 4. The imaging system of claim 1, furthercomprising a display device configured to display video images derivedfrom image data captured by the camera.
 5. The imaging system of claim4, wherein the display device displays images derived from image datacaptured by the camera during the first illumination period and does notdisplay images derived from image data captured by the camera during thesecond illumination period.
 6. The imaging system of claim 1, furthercomprising an image processor that is operable to process image datacaptured by the camera to remove image data captured by the cameraduring the second illumination period.
 7. The imaging system of claim 6,wherein the image processor processes image data captured by the cameraduring the first illumination period to detect objects present in theregion that is at least in part encompassed by the field ofillumination.
 8. The imaging system of claim 1, wherein the light sourcecontrol operates the at least one light source in a repeating cycle thatrepeats sufficiently frequently such that the at least one light source,when disposed at the rear portion of the equipped vehicle and whencycled, appears to onlookers to be illuminated at a constant thirdbrightness level that is lower than the first brightness level andhigher than the second brightness level.
 9. The imaging system of claim8, wherein the repeating cycle repeats at least about 30 times persecond.
 10. The imaging system of claim 1, wherein the camera controlreceives timing signals from the light source control indicative of whento operate the camera to capture image data and when to operate thecamera to not capture image data.
 11. An imaging system for capturingimages rearward of a vehicle, the imaging system comprising: a tail lampassembly configured for mounting at a rear portion of a vehicle equippedwith the imaging system, wherein the tail lamp assembly includes atleast one light source operable to emit light, wherein, with the taillamp assembly mounted at the equipped vehicle and with the at least onelight source activated, the tail lamp assembly emits light thatilluminates a field of illumination rearward of the equipped vehicle; acontrol operable to operate at least one light source of the tail lampassembly in a repeating cycle that includes (i) a first illuminationperiod wherein light emitted by the tail lamp assembly has a firstbrightness level, and (ii) a second illumination period wherein lightemitted by the tail lamp assembly has a second brightness level that islower than the first brightness level; a camera operable to captureimage data representative of a region that is at least in partencompassed by the field of illumination; wherein the camera capturesimage data during at least part of the first illumination period andduring at least part of the second illumination period; and an imageprocessor operable to process image data captured by the camera, whereinthe image processor receives image data captured by the camera duringboth the first and second illumination periods and removes image datacorresponding to image data captured by the camera during the secondillumination period.
 12. The imaging system of claim 11, wherein the atleast one light source of the tail lamp assembly is deactivated duringthe second illumination period.
 13. The imaging system of claim 11,further comprising a display device, wherein the display device displaysvideo images derived from image data captured by the camera.
 14. Theimaging system of claim 13, wherein the display device displays imagesderived from image data captured by the camera during the firstillumination period and does not display images derived from image datacaptured by the camera during the second illumination period.
 15. Theimaging system of claim 11, wherein the image processor processes imagedata captured by the camera during the first illumination period todetect objects present in the region that is at least in partencompassed by the field of illumination.
 16. The imaging system ofclaim 11, wherein the control operates the at least one light source ina repeating cycle that repeats sufficiently frequently such that the atleast one light source, when disposed at the rear portion of theequipped vehicle and when cycled, appears to onlookers to be illuminatedat a constant third brightness level that is lower than the firstbrightness level and higher than the second brightness level.
 17. Theimaging system of claim 16, wherein the repeating cycle repeats at leastabout 30 times per second.
 18. An imaging system for capturing imagesrearward of a vehicle, the imaging system comprising: a tail lampassembly configured for mounting at a rear portion of a vehicle equippedwith the imaging system, wherein the tail lamp assembly includes aplurality of light emitting diodes operable to emit light and wherein,with the tail lamp assembly mounted at the equipped vehicle and with atleast one of the plurality of light emitting diodes activated, the taillamp assembly emits light that illuminates a field of illuminationrearward of the equipped vehicle; a light source control operable tooperate at least one light emitting diode of the tail lamp assembly in arepeating cycle that includes (i) a first illumination period whereinlight emitted by the tail lamp assembly has a first brightness level,and (ii) a second illumination period wherein light emitted by the taillamp assembly has a second brightness level that is lower than the firstbrightness level; wherein the repeating cycle repeats at least about 30times per second; a camera operable to capture image data representativeof a region that is at least in part encompassed by the field ofillumination; a camera control operable to control the camera, whereinthe camera control operates the camera to capture image data during atleast part of the first illumination period and wherein the cameracontrol operates the camera to not capture image data during at leastpart of the second illumination period; and a display device configuredto display video images derived from image data captured by the camera,wherein the display device displays images derived from image datacaptured by the camera during the first illumination period and does notdisplay images derived from image data captured by the camera during thesecond illumination period.
 19. The imaging system of claim 18, whereinthe light source control deactivates the at least one light source ofthe tail lamp assembly during the second illumination period, andwherein the camera control operates the camera to not capture image dataduring the second illumination period.
 20. The imaging system of claim18, further comprising an image processor that is operable to processimage data captured by the camera to remove image data captured by thecamera during the second illumination period, wherein the imageprocessor processes image data captured by the camera during the firstillumination period to detect objects present in the region that is atleast in part encompassed by the field of illumination.